The present invention relates to a process for the extraction of lactones from a lactone-containing lipid material, by contacting a medium, having a temperature near the critical temperature of said medium, and having a pressure near the critical pressure of said medium, with the lipid material, and subsequently removing the medium.
The above process is known from European patent application no. 82201077.3 (Unilever) In said application the fractionation of butterfat, by means of supercritical carbon dioxide, is disclosed. It is also mentioned that the extracted fraction was enriched in lactones. The extraction was carried out by means of supercritical carbon dioxide at a pressure of 200 bar and a temperature of 80.degree. C. The lactone-enriched fraction obtained constituted about 19 wt. % of the original product.
Japanese application 62/134042, describes a method of preparing butterfat of low cholesterol content, by extracting butterfat with supercritical carbondioxide, at a temperature of 40.degree. C. and pressures of 300-350 kg/cm.sup.2 (294.3-333.4 bar), and subsequently contacting the extracted butterfat with a silicic acid column.
In Journal of Food Science, 52 (1987), 1231 the fractionation of milkfat with supercritical carbondioxide at temperatures of 50.degree. C. and 70.degree. C., over a pressure range of 100-350 bar, is mentioned.